• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.3
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• pp.17-24
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• 2016

The reacting flows of gaseous hydrogen/liquid oxygen 2D coaxial shear injector with varying recess length are numerically analyzed. The standard ${\kappa}-e$ model and laminar flamelet model are adopted for the steady turbulent combustion with the ideal and real gas equations. As the recess length increases, the recirculating region in the combustion chamber expands and the vorticity is intensified. Also, the variations of temperature, products, and pressure are strongly related to the recess length. The results show that an efficient combustor can be obtained by the introduction of the recessed injector.

• Environmental Engineering Research
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• v.25 no.4
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• pp.479-487
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• 2020

Current assumptions are used in the formulation of pseudo-first (PFO) and second-order (PSO) models to describe the kinetic data of filtration based on ideal operating conditions. This paper presents a new model developed with pseudo n^th order and based on real assumption. A comparison was performed between PFO, PSO and the new model to highlight their performance and the optimisation of the pseudo-order equation, using MATLAB software. Adsorption characteristic of bovine serum albumin adsorption on the track-etched membrane are used as a medium based on protein filtration data were extracted from the literature for different concentrations to demonstrate the comparison between PFO/PSO and the new model. The pseudo first and second-order kinetic models were applied to test the experimental data and they did not provide reasonable values. The results show that the predicted values are consistent with experimental values giving a good correlation coefficient R² = 0.997 and a minimum root mean squared error RMSE = 0.0171. Indeed, the experimental results follow the new model and the optimal pseudo equation order n = 1.115, the most suitable curves for the new model. As a result, we used different experimental adsorption data from the literature to examine and check the applicability and validity of the model.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.3233-3235
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• 2000

A new method for HRV(heart rate variability} detection from the R-wave signal, based on the IPFM (integral pulse frequency modulation) model and its similarity to pulse position modulation, is presented. The proposed method exert lowpass filtering with a Kaiser window. In this paper, The proposed method presents a powerful, but simple, tool for investigation of HRV. It also guarantees real-time behavior, simplicity in design, and phase linearity. Even without the basic assumption of IPFM model, the new algorithm can still be used on-line and with higher performance. It is thoroughly proved that lowpass filtering is an ideal method for PSD (Power Spectrum Density) analysis of HRV.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.6
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• pp.115-123
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• 2011

Most of cameras being used in practice induce lens distortion; the amount of distortion depends on the specific applications as well as the camera cost. Up to now, many methods of lens distortion correction have relied on invariant properties of projective geometry to find distortion parameters. A common property is "the straight line in scene is straight line in image". However, if the straight lines are also parallel together, the previous works have missed this restriction in determining lens distortion parameters. In this paper, we propose a method that leads to guarantee of the restrictions simultaneously for the determination. Therefore, corrected image will close to an ideal image taken by the pinhole camera model. The effectiveness of the proposed method is verified by our experiments on both synthetic images and real images.

• Journal of Korean Society of Forest Science
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• v.106 no.2
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• pp.267-273
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• 2017

This study was conducted to construct a empirical yield table for Pinus densiflora in real forest. Since existing normal yield tables have been derived by studying and analyzing communities in ideal environment for tree growth, those tables provide more over-estimated values than ones from real forest. Because of this, there are some difficulties to apply the tables to empirical forest except for normal forest. In this study, therefore, we estimated stand growth for real forest on P. densiflora as the representative species of conifers. We used 1,957 sample plot data of P. densiflora in central Korea from National Forest Inventory (NFI) system, and analyzed through estimation, recovery and prediction in order by using Weibull function as a diameter distribution model. Weilbull and Schumacher models were applied for estimating mean DBH and mean basel area and it was found that the site index for P. densiflora in central Korea ranges from 8 to 14 at reference age 30. According to site 12 in the stand yield table, the Mean Annual Increment (MAI) of P. densiflora was $4.42m^3/ha$ at 30 years of age. Compared to existing volume table constructed before, it is showed that MAI of this study were lower. According to the paired t-test that is conducted with the gap of volume values between normal forest and real forest by site index and age, the P-value was less than 0.001 which is recognized to have a statistically significant difference. Based on the results in this study, it is considered to be helpful for practical management and management policy on P. densiflora in central Korea.

• Journal of The Korean Association For Science Education
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• v.27 no.4
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• pp.309-317
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• 2007

The purpose of the study is to investigate the effects of problem solving models and middle school students' recognition inproblem solving activities and to get implications of problem solving activities in science education. We took the position of problem solving as consisting of four sequential stages: search of problems, performance of the plan, presentation of results, and evaluation of the presentation. Taking into account thechosen activity factors for each stage of problem solving, we developed detailed activity tools that are supposed to guide the stage. Recognition of problem solving activities in 7th grade middle school students were positive. Students felt that problem solvingactivities made them engage more and interested in science classes, and that they were helpful in solving problems in everyday life. Even though they found real problems in everyday life, they preferred problem solving activities to deal with real problems rather than simple minded ones.

• Journal of Digital Convergence
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• v.13 no.9
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• pp.183-189
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• 2015

In this paper, we propose an object tracking method using the color information of the image in surveillance network. This method perform a object detection using of adaptive color model. Object contour detection plays an important role in application such as object recognition. Experimental results demonstrate successful object detection over a wide range of object's variation in color and scale. In applications to detect an object in real time, when transmitting a large amount of image data it is possible to find the mode of a color distribution. The specific color of an object is modified at dynamically changing color in image. So, this algorithm detects the tracking area information of object within relevant tracking area and only tracking the movement of that object.Through experiments, we show that proposed method is more robust than other methods under certain ideal situations.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.2 s.152
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• pp.148-153
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• 2007

Two typical impact loadings, shock wave and gas bubble pulse, due to UNDEX(UNDerwater EXplosion), should be considered together for the closest response analysis of structure subjected to UNDEX to a reality. Since these two impact loadings have different response time bands, however, their response characteristics of structure are different from each other. It is impossible to consider these effectively under the current computational environment and the mathematical model has not yet been developed. Whereas Hicks model approximates the fluid-structure interaction due to gas bubble pulse as virtual mass effect, treating the flow by the response of gas bubble after shock wave as incompressible ideal fluid contrary to the compressible flow due to shock wave, Geers-Hunter model could make the closest response analysis of structure under UNDEX to a real one as a mathematical model considering the fluid-structure interaction due to shock wave and gas bubble pulse together using acoustic wave theory and DAA(Doubly Asymptotic Approximation). In this study, the application and effectiveness of integrated dynamic response analysis of submerged structure was examined with the analysis of the shock wave and gas bubble pulse together.

• The Korean Journal of Community Living Science
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• v.19 no.3
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• pp.431-444
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• 2008

Today people obtain much information about appearances through movies. The stars' body images in movies have been created through total fashion as they play the roles of an ideal model to create actual body images. This study examined the relations between the body images in the film media in terms of appearances or total fashion and actual body images based on the simulation theory by Jean Baudrillard. It conducted a literature study by collecting and analyzing film media-related picture images from books, papers, periodicals and the Internet home and abroad. The research scope was limited to the stars who made appearances in movies and the ones who starred in movies in addition to their other lines of work. As a result, the following conclusions were drawn; the stars' body images went hyperreal between their actual body images and the ones of their roles in movies and then were simulated in fashion. To be specific, 1. the stars' actual body images went hyperreal and were simulated in fashion in the following cases; 1) the stars in the heyday of film; 2) fashionistas; and 3) pictures taken by paparazzi. 2. The body images of their roles went hyperreal in the following cases; 1) through brand participation; 2) through changed body images; and 3) through cyber body images. Their body images became hyperreal and were simulated in fashion by the input of fashion designers and the techniques of other areas. The body images in film are the object of desire to the audience. They go hyperreal and become the ideal body image to real people. The various kinds of hyperreal images in the film media create new beauty as a reference and object of comparison for people to change their body images in reality.

• Cross-Cultural Studies
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• v.22
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• pp.7-27
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• 2011

This article is devoted to little-studied play of M.A. Bulgakov "Adam and Eve". By the end of 1920's - the beginning of 1930's soviet society is differentiated again, its construction is rebuilded. In the new condition drama is needed as much as possible. Drama on the stage is ideal model for instruction of "Mass". Thereupon soviet society asked "New Hero", "New play", which can rebuild soviet citizen in the new construction of government. Thereby the play of M.A. Bulgakov "Adam and Eve" is created by order of soviet society. In this play typical soviet people are represented: Adam Krasovsky(engineer), Daragan(pilot-terminator), Ponchik-Nepobeda(writer), Zahar Markizov(proletarian-baker). They are different from each other by their occupation and formation, but they have same consciousness and they think identically. Bulgakov makes stand such problems: impersonality and unfreedom of human being in the government of communism. Bulgakov, using Parody, doubt the possibility of realization of utopia of Soviet government. Bulgakov show to us that Adam Krasocsky is not real Adam-first human being. In the play we can see the real Adam is the scientist-intelligent Efrosimov. Bulgakov change the place of Ponchik with the place of Markizov. The idiot and the fool is recognized not Markisov-drinker, tyrant, but Ponchik-writer. After the disaster Markisov, reading a Bible, is changing and by the end of play he started writing his own novel. Indeed if Ponchik wrote hoked-up novel, Markisov writes a real own history. Request of Leningrad Theater for Bulgakov to write about the future war comes from the spirit of the time. But Bulgakov in this play "Adam and Eve" could insist that the "Life" is a supreme value.